1. Field of the Invention
The present invention relates to a process cartridge and an electrophotographic image forming apparatus detachably attachable with the process cartridge.
2. Related Background Art
Examples of an electrophotographic image forming apparatus includes, for example, an electrophotographic copying machine, an electrophotographic printer (for example, a LED printer, a laser printer and the like), an electrophotographic facsimile, an electrophotographic word processor and the like.
Further, the process cartridge includes an electrophotographic photosensitive body and at least one of charging means, developing means and cleaning means that are integrally turned into a cartridge as process means so as to be detachably attachable with an electrophotographic image forming apparatus main body. Or, furthermore, at least developing means and the electrophotographic photosensitive body are integrally turned into a cartridge as process means and detachably attachable with the electrophotographic image forming apparatus main body.
Conventionally, in the electrophotographic image forming apparatus using an electrophotographic image forming process, a process cartridge system is adopted, wherein an electrophotographic photosensitive body and process means acting on the electrophotographic photosensitive body are integrally incorporated into a cartridge, and this cartridge is made detachable and attachable with the image forming apparatus main body. According to this process cartridge system, maintenance of the apparatus can be performed by a user himself or herself without depending on a service person, so that operability can be exceptionally improved. Hence, this process cartridge system is widely used in the image forming apparatus.
Further, in this type of the process cartridge system, for example, as described in Japanese Patent Laid-Open No. 9-179476, a process cartridge system is proposed, wherein storage means such as an IC memory and the like for storing information to be transmitted to the image forming apparatus main body is mounted on the process cartridge, and the information is exchanged with the apparatus main body when the process cartridge is loaded on the apparatus main body, so that the using conditions and the like of the process cartridge are reported to a control portion of the apparatus main body. Further, a lot number of the process cartridge, a characteristic of the image forming apparatus, and a characteristic of the process means are registered in the storage means mounted on the process cartridge, maintenance of the image forming apparatus or the process cartridge becomes easy, and further, an image forming control was performed according to the information registered in the storage means, so that the image forming operation was performed under the best condition.
In the image forming apparatus adopting such a process cartridge, as connecting means for electrically connecting the storage means mounted on the process cartridge and the apparatus main body, there are available a contact type for connection by using a contact by means of a connector or a spring material and a non-contact type for communication by using a light-emitting element and a light-receiving element or by a wireless method by means of magnetic induction of inductor inductance via a magnetic core. Among these means, contact type connecting means using the spring material is simple in the constitution, is advantageous cost-wise and is generally used.
However, in the above-described conventional art using the contact type connecting means, the electrical connection between the storage means of the process cartridge and the image forming apparatus main body is sometimes unstable as described below.
The process cartridge attached onto the apparatus main body generates movement in a rotational direction with a photosensitive body drum as a center and movement in a thrust direction of the photosensitive body drum at the operation starting time and the operation stopping time of the apparatus. Usually, an electrical contact pressure is secured in a state in which a driving force is applied to the process cartridge from the apparatus main body. For this reason, in a state in which a driving force is applied and not applied, there was a possibility of causing a change in the posture of the process cartridge, thereby causing irregularity of electrical contact pressure.
Hence, the present invention has been made in view of the above-described unsolved problems of the prior art.